Features: 100% brand new and high quality Practical and durable home using product Increase oxygen levels, lower CO2 and raise PH. It is an important instrument to successfully keep aquatic fish for respiration process. Durable, washable and sintered by high temperature. Creates bubbles in fish tank while attached to an air pump(air pump is not included). Creates water currents and dazzling underwater scenes. Perfect accessories for better life Green mineral stone, non-toxic, safe for use Help to keep fish healthy and adds extra beauty to the aquarium Usage: Please soak the air stones in water for about 30 minutes before usage. After a long-term use, clean your stone regularly so that it will be most effective. Replacing the air stone every six months. Specifications: Type: Turtle Shape Material: Mineral stone+Plastic Color: Blue Size: 6.5x4cm Quantity: 1 Pc Note: 1.Transition: 1cm=10mm=0.39inch 2.Please allow 0-3cm error due to manual measurement. pls make sure you do not mind before you bid. 3.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! No Retail Package Package Contents: 1 Pc x Air Bubble Stone